Dielectric composition and electronic component

ABSTRACT

A dielectric composition containing a complex oxide represented by the formula of A α B β C 2γ O α+β+5γ  as the main component, wherein A represents Ba, B represents at least one element selected from the group consisting of Ca and Sr, C represents at least one element selected from the group consisting of Ta and Nb, and α, β and γ meet the following conditions, i.e., α+β+γ=1.000, 0.000&lt;α≦0.375, 0.625≦β&lt;1.000, 0.000≦γ≦0.375.

The present invention relates to a dielectric composition and anelectronic component.

BACKGROUND

The MIMO (Multi-Input Multi-Output) technique which simultaneouslyutilizes a plurality of frequency bands has been put into use so as toprovide a communication with a higher speed and a larger capacity inmobile communicating equipment which is represented by a smart phone ora tablet. Since each frequency band needs a RF component, if thefrequency bands for communication are increased in number, in order tomaintain the original size of the equipment where increased componentsare disposed, each component needs to be further downsized and providedwith more functions.

Such an electronic component working at a high frequency can be, forexample, a diplexer, a band-pass filter or the like. All of thesecomponents contain the combination of dielectric material(s) functioningas capacitor and magnetic material(s) functioning as inductor. In orderto provide good high-frequency characteristics, each kinds of loss at ahigh-frequency region are required to be suppressed.

The requirements for the dielectric material are as follows. (1)According to the requirements for downsizing, the relative permittivity(∈r) is required to be high in order to decrease the area of thecapacitor. (2) The dielectric loss is required to be low, i.e., the Qvalue is required to be high in order to obtain a good selectivity infrequencies. (3) The breakdown voltage is required to be high.

For example, generally speaking, the Q value of the amorphous film ofSiNx under a high frequency (2 GHz) is as high as about 500, and thebreakdown voltage is as high as about 500 to 700 V/μm, thus, it can bewidely used in the electronic components using under the high frequency.However, its relative permittivity (∈r) is as low as about 7, so a largearea is needed to provide the target functions. In this respect, it ishard to meet the downsizing requirements.

In Non-Patent Document 1, in the CaZrO₃ film, a Ca—Zr—O amorphous filmis formed by providing an annealing process after the film deposition.At this time, it is reported that the relative permittivity at 100 kHzof the Ca—Zr—O amorphous film is 12.8˜16.0, and the Q value is 370 to555.

Non-Patent Document

Non-Patent Document 1: Science direct Physica B, 348(2004) 440-445,Preparation and characterization of sol-gel derived CaZrO₃ dielectricthin film for high-k applications.

SUMMARY

In Non-Patent Document 1, the Q value is 370 to 555 at a measuringfrequency of 100 kHz, and is 200 or below at a measuring frequency of 1MHz. A tendency of the decreasing of the Q value accompanying with theincreasing of the measuring frequency can be observed, thus, it can bepredicted that the Q value will further decrease under 2 GHz. Inaddition, the breakdown voltage is as low as 260V/μm. As a result, therelative permittivity will be about 2 times or higher compared with theamorphous SiNx while the Q value and the breakdown voltage will not beimproved.

The present invention has been completed in view of the actualconditions mentioned above. The present invention aims to provide adielectric composition with a high relative permittivity, a high Qvalue, and a high breakdown voltage even under a field of a highfrequency (2 GHz) and also an electronic component using the dielectriccomposition.

In order to achieve the mentioned aim, the dielectric compositionaccording to the present invention is characterized in that it comprisesa complex oxide represented by the formula of A_(α)B_(β)C_(2γ)O_(α+β+5γ)(wherein A represents Ba, B represents at least one element selectedfrom the group consisting of Ca and Sr, and C represents at least oneelement selected from the group consisting of Ta and Nb) as the maincomponent, wherein α, β and γ meet the following relationship,α+β+γ=1.000, 0.000<α≦0.375, 0.625≦β<1.000 and 0.000≦γ≦0.375.

A high relative permittivity, a high Q value and a high breakdownvoltage can be obtained even under the field of a high frequency (2 GHz)when the α, β and γ are within the range mentioned above.

Further, compared to the conventional dielectric composition used in anelectronic component working at a high frequency, the use of thedielectric composition of the present invention can satisfy therequirements of downsizing because it can obtain a sufficiently highrelative permittivity under a high frequency (2 GHz). Further, as the Qvalue is higher than the conventional dielectric composition, i.e., ahigher S/N ratio is obtained, and further, the breakdown voltage ishigh, thus, an electronic component such as a dielectric resonator or adielectric filter with a better performance can be provided.

According to the present invention, a dielectric composition with a highrelative permittivity and Q value under a high frequency (2 GHz) and ahigh breakdown voltage can be provided and also an electronic componentusing the dielectric composition.

BRIEF DESCRIPTION OF THE DRAWINGS

The FIGURE is a cross-sectional view of a film capacitor in oneembodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

(Film Capacitor 10)

The FIGURE is a cross-sectional view of film capacitor 10 as an exampleof the electronic component using the dielectric composition in oneembodiment of the present invention. Film capacitor 10 is provided withlower electrode 3, upper electrode 4 and dielectric film 5 disposedbetween lower electrode 3 and upper electrode 4, which three arelaminated on the surface of supporting substrate 1. Foundation layer 2is provided between supporting substrate 1 and lower electrode 3 toenhance the adhesion between them. Supporting substrate 1 guarantees thewhole mechanical strength of film capacitor 10.

The shape of the film capacitor is not particularly restricted and isusually cuboid. Further, its size is not particularly restricted. Thethickness or the length can be appropriately set in accordance withspecific uses.

(Supporting Substrate 1)

There is no particular restriction on the material for formingsupporting substrate 1 as shown in the FIGURE. For example, substrate ofsingle crystals such as single crystalline Si, single crystalline SiGe,single crystalline GaAs, single crystalline InP, single crystallineSrTiO₃, single crystalline MgO, single crystalline LaAlO₃, singlecrystalline ZrO₂, single crystalline MgAl₂O₄ and single crystallineNdGaO₃, or ceramic polycrystalline substrate such as polycrystallineAl₂O₃, polycrystalline ZnO and polycrystalline SiO₂, or metals such asNi, Cu, Ti, W, Mo, Al, Pt or the like or the alloys thereof can formsupporting substrate 1, but there is no particular restriction. Amongthese materials, the single crystalline Si is usually used as thesubstrate from the viewpoint of the low cost and good processabilities.The resistivity of supporting substrate 1 varies depending on thematerial of the substrate. When a material having a low resistivity isused as the substrate, the leakage of the current flowing towards thesubstrate side will affect the electric properties of film capacitor 10if such a substrate is directly used. Thus, sometimes an insulatingtreatment can be performed on the surface of supporting substrate 1 soas to prevent the current in use from flowing to supporting substrate 1.For example, when the single crystalline Si is used as supportingsubstrate 1, the surface of supporting substrate 1 can be oxidized toform an insulating layer of SiO₂. Alternatively, insulating materialssuch as Al₂O₃, SiO₂, Si₃N_(x) or the like can be formed on the surfaceof supporting substrate 1. The material or the film thickness for theinsulating layer is not restricted as long as supporting substrate 1 canbe kept to be insulated. However, the film thickness is preferred to be0.01 μm or more. A thickness less than 0.01 μm cannot ensure theinsulation and thus is not preferred as the thickness of the insulatinglayer. There is no particular restriction on the thickness of thesupporting substrate 1 as long as the mechanical strength of the wholefilm capacitor can be ensured. For example, the thickness can be set tobe 10 μm to 5000 μm. When the thickness is thinner than 10 μm, themechanical strength may not be ensured. On the other hand, if thethickness is thicker than 5000 μm, a problem may be caused that itcannot contribute to the downsizing of the electronic component.

(Foundation Layer 2)

In the present embodiment, it is preferred to have foundation layer 2 onthe surface of supporting substrate 1 which has been provided with aninsulating treatment. Foundation layer 2 is inserted to enhance theadhesion between supporting substrate 1 and lower electrode 3. As anexample, Cr is usually inserted as foundation layer 2 when Cu is used inlower electrode 3 and Ti is usually inserted as foundation layer 2 whenPt is used as lower electrode 3.

Foundation layer 2 is not restricted to the above materials listed asexamples because the purpose is to improve the adhesion betweensupporting substrate 1 and lower electrode 3. In addition, foundationlayer 2 can be omitted if the adhesion between supporting substrate 1and lower electrode 3 can be guaranteed.

(Lower Electrode 3)

The material for forming lower electrode 3 is not particularlyrestricted as long as it is conductive. For instance, lower electrode 3can be formed by metals such as Pt, Ru, Rh, Pd, Ir, Au, Ag, Cu, Ni andthe like or the alloys thereof or the conductive oxides thereof. In thisrespect, a material can be selected in accordance with the cost or theatmosphere during the thermal treatment for dielectric film 5. Inaddition to air, the thermal treatment for dielectric film 5 can also becarried out in an inert gas such as N₂ or Ar, or a mixed gas of an inertgas and a reductive gas H₂. The film thickness of lower electrode 3 isnot particularly restricted as long as lower electrode 3 can function asan electrode. Further, the thickness is preferred to be 10 nm or more. Athickness less than 10 nm is not preferable because the conductivitywill deteriorate in that case. In addition, when a substrate composed ofCu, Ni, Pt or the like or a conductive oxide material, which can be usedas an electrode, is used as supporting substrate 1, foundation layer 2and lower electrode 3 mentioned above can be omitted.

Lower electrode 3 is preferably formed by various film-depositionmethods such as vacuum evaporation, sputtering, PLD (Pulsed laserdeposition), MO-CVD (Metal-organic chemical vapor deposition), MOD(Metal organic decomposition) or Sol-Gel, CSD (Chemical solutiondeposition) or the like. At that time, a trace of impurities orsubcomponents may be contained in the starting material in use (i.e.,the deposition material, various target materials, organometalicmaterial and etc.), but no particular problem will arise as long as theyare not impurities which will significantly deteriorate theconductivity.

A thermal treatment can be provided after the formation of the lowerelectrode 3 so as to improve the adhesion between foundation layer 2 andlower electrode 3 and also to improve the stability of lower electrode3. When the thermal treatment is performed, the heating rate ispreferably 10° C./min to 2000° C./min, and more preferably 100° C./minto 1000° C./min. The holding temperature during the thermal treatment ispreferably 400° C. to 800° C., and the holding time is preferred to be0.1 hour to 4.0 hours. If any parameter goes beyond the ranges mentionedabove, the adhesion will not be good and the surface of lower electrode3 will be uneven so that the dielectric properties of dielectric film 5is likely to deteriorate.

(Dielectric Film 5)

The dielectric composition for forming dielectric film 5 comprises acomplex oxide represented by the formula of A_(α)B_(β)C_(2γ)O_(α+β+5γ)(wherein A represents Ba, B represents at least one element selectedfrom the group consisting of Ca and Sr, and C represents at least oneelement selected from the group consisting of Ta and Nb) as the maincomponent.

Further, α, β and γ of the dielectric composition meet the followingrelationship, i.e., α+β+γ=1.000, 0.000<α≦0.375, 0.625≦β<1.000 and0.000≦γ≦0.375.

As the oxides of Ca or Sr which constitutes B of the formula, CaO or SrOare materials with high Q value and high breakdown voltage, but there isa problem for its low relative permittivity. Thus, in order to improvethe relative permittivity, the inventors of the present invention findthat the relative permittivity can be improved without decreasing thealready obtained Q value and breakdown voltage by containing properamount of BaO in the dielectric composition containing the mentioned CaOor SrO.

Further, it is found that the moisture resistance is improved bycontaining proper amount of Ta or Nb which constitutes C of the formula.

A dielectric composition with a high relative permittivity, a high Qvalue and a high breakdown voltage under a high frequency (2 GHz) can beobtained by controlling the relationship of α, β and γ of the dielectriccomposition meet the following relationship, i.e., α+β+γ=1.000,0.000<α≦0.375, 0.625≦β<1.000 and 0.000≦γ≦0.375. It is preferred thatα+β+γ=1.000, 0.005≦α≦0.375, 0.625≦β≦0.995 and 0.000≦γ≦0.375. On theother hand, if a is more than 0.375, a high Q value cannot be obtainedand when α=0, an expected relative permittivity cannot be obtained. Inaddition, when β is less than 0.625, a high Q value cannot be obtained.Further, if γ exceeds 0.375, excessive Ta or Nb will form a differentphase and the different phase will exist in the grain boundary in alarge amount, thus, the high Q value cannot be maintained.

In addition, the relationship of α, β and γ of the dielectriccomposition is preferred to be as follows, i.e., α+β+γ=1.000,0.000≦α≦0.375, 0.625≦β≦1.000 and 0.000≦γ≦0.375. That is, it is preferredto contain proper amount of Ta or Nb which constitutes C in the formula.

In this way, a dielectric composition can be obtained which can possessa high relative permittivity, a high Q value and a high breakdownvoltage under a high frequency (2 GHz) and further have a high moistureresistance. That is, when the dielectric composition was provided with apressure cooker test under a condition with a temperature of 121° C., ahumidity of 95% RH and a pressure of 2 atm for 100 hours, the dielectriccan still show an approximately equal character as the initialcharacter.

In addition, in order to obtain a higher relative permittivity, therelationship of α, β and γ is preferred to be as follows, i.e.,α+β+γ=1.000, 0.100≦α≦0.375, 0.625≦β≦0.900 and 0.000<γ≦0.275, and morepreferably 0.100≦α≦0.375, 0.625≦β≦0.895 and 0.005≦γ≦0.275.

Further, in order to obtain a higher Q value, the relationship of α, βand γ is preferred to be as follows, i.e., α+β+γ=1.000, 0.000<α≦0.180,0.770≦β<1.000 and 0.000<γ≦0.050, and more preferably 0.005≦α≦0.180,0.770≦β≦0.990 and 0.005≦γ≦0.050.

Further, in order to obtain a higher breakdown voltage, the relationshipof α, β and γ is preferred to be as follows, i.e., α+β+γ=1.000,0.000<α≦0.215, 0.770≦β<1.000 and 0.000<γ≦0.015, and more preferably0.005<α≦0.215, 0.770≦β≦0.990 and 0.005≦γ≦0.015.

Further, the relationship of α, β and γ is preferred to be as follows,i.e., α+β+γ=1.000, 0.100≦α≦0.180, 0.805≦β≦0.900 and 0.000<γ≦0.015, andmore preferably 0.100≦α≦0.180, 0.805≦β≦0.895 and 0.005≦γ≦0.015. In thisway, the relative permittivity, the Q value and the breakdown voltagecan all be increased.

The thickness of the dielectric film 5 is preferably 10 nm to 2000 nm,and more preferably 50 nm to 1000 nm. If the thickness is less than 10nm, the dielectric breakdown is likely to happen. When the thicknessexceeds 2000 nm, the area of the electrode needs to be broadened so asto enlarge the electrostatic capacity of the capacitor, and it may behard to downsize according to the designs of the electronic component.In the measurement of the thickness of the dielectric film, theelectronic component can be milled by a processing device involving FIB(focused ion beam), and then the obtained cross-section is observed byan SIM (scanning ion microscope) to measure the thickness.

Dielectric film 5 is preferably formed by various deposition methodssuch as vacuum evaporation, sputtering, PLD (Pulsed laser deposition),MO-CVD (Metal-organic chemical vapor deposition), MOD (Metal organicdecomposition) or Sol-Gel, CSD (Chemical solution deposition) or thelike. At that time, a trace of impurities or subcomponents may becontained in the starting material in use (i.e., the depositionmaterial, various target materials, organometalic material and etc.),but no particular problem will arise as long as they are not impuritieswhich will significantly deteriorate the insulation properties.

Further, a trace of impurities or subcomponents may be contained in thedielectric composition as long as they are not matters which willsignificantly deteriorate the effect of the present invention (i.e., therelative permittivity, the Q value, or the breakdown voltage). Thus, theamount of the main component as the balance is not particularlyrestricted. For example, the amount of the main component is 50 mol % ormore and 100 mol % or less relative to the whole dielectric compositioncomprising the main component.

In addition, the dielectric film 5 usually contains the dielectriccomposition of the present invention as the main component, but it canalso be a laminated structure in combination with films made of otherdielectric compositions. For example, by making into a laminatedstructure with the conventional amorphous dielectric films or thecrystalline films such as SiN_(x), SiO_(x), AlO_(x), ZrO_(x), TaO_(x) orthe like, the impedance or the temperature dependence of relativepermittivity of the dielectric film 5 can be adjusted.

(Upper Electrode 4)

In one example of the present embodiment, film capacitor 10 is providedwith upper electrode 4 on the surface of dielectric film 5, whereinupper electrode 4 functions as another electrode in film capacitor 10.The material for forming upper electrode 4 is not particularlyrestricted as long as it is conductive. Upper electrode 4 can be formedby the same material as that for lower electrode 3. Also, the filmthickness of upper electrode 4 is not particularly restricted as long asthe function as an electrode can be exerted, and the thickness ispreferred to be 10 nm or more. A film thickness of 10 nm or less is notpreferable for upper electrode 4 because the conductivity willdeteriorate in that case.

Upper electrode 4 is preferably formed by various film-depositionmethods such as vacuum evaporation, sputtering, PLD (Pulsed laserdeposition), MO-CVD (Metal-organic chemical vapor deposition), MOD(Metal organic decomposition) or Sol-Gel, CSD (Chemical solutiondeposition) or the like. At that time, a trace of impurities orsubcomponents may be contained in the starting material in use (i.e.,the deposition material, various target materials, organometalicmaterial and etc.), but no particular problem will arise as long as theyare not impurities which will significantly deteriorate theconductivity.

In the embodiment mentioned above, a film capacitor is presented as anexample of the electronic component using the dielectric compositionaccording to one embodiment of the present invention. However, theelectronic component using the dielectric composition of the presentinvention is not limited to the film capacitor and also can be anyelectronic component having a dielectric film such as a diplexer, aband-pass filter, a balun or a coupler.

EXAMPLES

Hereinafter, the present invention will be further described based ondetailed examples, but the present invention is not limited to theseexamples.

Example 1 (Comparative Example 1)

First of all, a Ti film as the foundation layer with a thickness of 20nm was deposited by a sputtering method on the surface of a squaresupporting substrate of 10 mm×10 mm with a thickness of 350 μm, wherein,the supporting substrate had a SiO₂ insulating film with a thickness of6 μm on the surface of Si.

Next, a Pt film as the lower electrode with a thickness of 100 nm wasdeposited by sputtering method on the deposited Ti film mentioned above.

The formed Ti/Pt film was provided with a thermal treatment at thenormal pressure under oxygen atmosphere with a heating rate of 400°C./min and a holding temperature of 700° C. for 0.5 hour.

The PLD method was used in the formation of the dielectric film. Thetargets necessary in the formation of the dielectric film were preparedas follow.

First, BaCO₃, CaCO₃, SrCO₃, Ta₂O₅ and Nb₂O₅ was weighed to get theamounts of Ba, Ca, Sr, Ta, and Nb in Sample No. 1 to Sample No. 36 asshown in Table 1. The weighed starting powders together with absoluteethanol and ZrO₂ beads of φ2 mm were put into a wide-mouth poly-pot of 1L and then subjected to wet mixing for 20 hours. Then, the slurry of themixed powder was dried at 100° C. for 20 hours. The obtained mixedpowder was put into a crucible made of Al₂O₃ and the pre-calcination wasperformed in air at 1250° C. for 5 hours to provide the pre-calcinedpowder.

A molded body was obtained by using a uniaxial pressing machine from theobtained calcined powder. The press condition was set with a pressure of2.0×10⁸ Pa and a temperature of room temperature.

After that, a sintering process was performed for the obtained moldedbody under atmospheric air with a heating rate of 200° C./hour and aholding temperature of 1600° C. to 1700° C. for 12 hours.

Next, the obtained sintered body was ground on both surfaces by using acylindrical grinding machine until the thickness became 4 mm, so thetarget for PLD necessary in the deposition of the dielectric film wasprepared.

Thus prepared target for PLD was used in the PLD method to form adielectric film with a thickness of 200 nm to 800 nm on the lowerelectrode. During the film-depositing using the PLD method, the oxygenpressure was controlled to be 1×10⁻¹ Pa and the substrate was heated to200° C. In addition, in order to expose part of the lower electrode, ametal mask was used to form an area where no dielectric film wasdeposited.

In the measurement of the thickness of the dielectric film, it wasmilled by FIB and then the resultant cross-section was observed by SIMto measure the thickness.

After deposition, the composition of the dielectric film was analyzed inall samples by using an XRF (X-ray fluorescence analyzer), and thecomposition was confirmed as described in Table 1.

Thereafter, a vapor deposition apparatus was used to deposit an Ag filmas the upper electrode on the obtained dielectric film. The upperelectrode was formed to have a diameter of 100 μm and a thickness of 100nm with the use of a metal mask, thus providing Sample No. 1 to SampleNo. 36 with the structure shown in the FIGURE.

As for all the obtained film capacitor samples, the relativepermittivity, the Q value and the breakdown voltage were respectivelymeasured by the following methods.

(Relative Permittivity and Q Value)

The relative permittivity and the Q value of the film capacitor sampleswere calculated based on the results from the measurement of theelectrostatic capacity and film thickness under a frequency of 2 GHz andan input signal level (measuring voltage) of 0.5 Vrms at a referencetemperature of 25° C. using an RF impedance/material analyzer (4991Aproduced by Agilent Technologies). The relative permittivity of theamorphous SiNx film was about 7. Thus, a relative permittivity of 11 ormore which is 1.5 times of that of the amorphous SiNx film was deemed asa good result. In addition, the Q value of the amorphous SiNx film wasabout 500. Thus, a Q value of more than 500 was deemed as a good result.

(Breakdown Voltage (Vbd))

As for all the film capacitor samples, a digital ultra-highresistance/micro current meters (ADVANTEST R8340) was connected with theexposed area of the lower electrode and also the upper electrode. Avoltage was applied in a step of 5V/second to perform the measurement,and the voltage value was read when the resistance value dropped bydouble digits from the initial resistance value. The value was regardedas the breakdown voltage value (the unit was V) of the sample. The valueobtained by dividing the breakdown voltage value (the unit was V) by thethickness of the dielectric film was deemed as the breakdown voltage Vbd(V/μm). In Table 1, the average value of n=5 was shown. The breakdownvoltage of the amorphous SiNx film was about 500 to 700 V/μm, thus, adielectric breakdown voltage of 700 V/μm or more was deemed as a goodresult.

As for all the obtained film capacitor samples, a pressure cooker test(PCT) under the following condition was performed as the moistureresistance test.

The film capacitor sample was put in a constant temperature bath with atemperature of 121° C., a humidity of 95% RH and a pressure of 2 atm for100 hours. Then, it was taken out from the constant temperature bath.The relative permittivity, the Q value and the dielectric breakdownvoltage were measured under the room temperature. If the relativepermittivity, the Q value and the dielectric breakdown voltage were allvalues within a range of ±5% compared with the value before the test andthe moisture resistance was also excellent, the result would be judgedas ⊚. If the relative permittivity, the Q value and the dielectricbreakdown voltage were all values within a range of ±10% compared withthe value before the test and the moisture resistance was good, theresult would be judged as ∘.

TABLE 1 relative Q film film Sample permittivity value Vbd moisturethickness forming No. A α B β C γ (—) (—) (V/μm) resistance (nm) methodExample 1 1 Ba 0.375 Ca 0.625 — 0.000 18 510 780 ◯ 400 PLD 2 Ba 0.005 Ca0.990 Ta 0.005 11 860 1240 ⊚ 400 PLD 3 Ba 0.005 Ca 0.995 — 0.000 11 8701250 ◯ 400 PLD 4 Ba 0.005 Ca 0.625 Ta 0.370 12 520 770 ⊚ 400 PLD 5 Ba0.100 Ca 0.900 — 0.000 14 820 1170 ◯ 400 PLD 6 Ba 0.100 Ca 0.625 Ta0.275 15 510 750 ⊚ 400 PLD 7 Ba 0.180 Ca 0.820 — 0.000 15 760 1180 ◯ 400PLD 8 Ba 0.180 Ca 0.770 Ta 0.050 16 750 840 ⊚ 400 PLD 9 Ba 0.005 Ca0.945 Ta 0.050 11 780 900 ⊚ 400 PLD 10 Ba 0.215 Ca 0.785 — 0.000 16 6301140 ◯ 400 PLD 11 Ba 0.215 Ca 0.770 Ta 0.015 16 600 1120 ⊚ 400 PLD 12 Ba0.005 Ca 0.980 Ta 0.015 11 800 1210 ⊚ 400 PLD 13 Ba 0.180 Ca 0.805 Ta0.015 15 760 1180 ⊚ 400 PLD 14 Ba 0.100 Ca 0.885 Ta 0.015 14 790 1120 ⊚400 PLD 15 Ba 0.050 Ca 0.760 Ta 0.190 13 610 920 ⊚ 400 PLD 16 Ba 0.190Ca 0.710 Ta 0.100 17 590 870 ⊚ 400 PLD 17 Ba 0.050 Ca 0.919 Ta 0.031 11790 990 ⊚ 400 PLD 18 Ba 0.050 Ca 0.942 Ta 0.008 11 800 1200 ⊚ 400 PLD 19Ba 0.140 Ca 0.829 Ta 0.031 15 770 1060 ⊚ 400 PLD 20 Ba 0.198 Ca 0.794 Ta0.008 16 720 1150 ⊚ 400 PLD 21 Ba 0.140 Ca 0.852 Ta 0.008 14 790 1240 ⊚400 PLD 22 Ba 0.140 Ca 0.852 Ta, Nb 0.008 14 770 1260 ⊚ 400 PLD 23 Ba0.140 Ca 0.852 Nb 0.008 14 760 1270 ⊚ 400 PLD 24 Ba 0.140 Ca, Sr 0.852Ta 0.008 15 780 1180 ⊚ 400 PLD 25 Ba 0.140 Ca, Sr 0.852 Ta, Nb 0.008 15770 1190 ⊚ 400 PLD 26 Ba 0.140 Ca, Sr 0.852 Nb 0.008 15 760 1210 ⊚ 400PLD 27 Ba 0.140 Sr 0.852 Ta 0.008 16 770 1130 ⊚ 400 PLD 28 Ba 0.140 Sr0.852 Ta, Nb 0.008 16 760 1150 ⊚ 400 PLD 29 Ba 0.140 Sr 0.852 Nb 0.00816 750 1160 ⊚ 400 PLD 30 Ba 0.140 Ca 0.852 Ta 0.008 14 780 1220 ⊚ 200PLD 31 Ba 0.140 Ca 0.852 Ta 0.008 14 800 1250 ⊚ 800 PLD Compara- 32 Ba0.410 Ca 0.590 — 0.000 18 480 720 ◯ 400 PLD tive 33 Ba 0.300 Ca 0.590 Ta0.110 20 450 670 ⊚ 400 PLD Example 34 Ba 0.150 Ca 0.590 Ta 0.260 14 440640 ⊚ 400 PLD 35 Ba 0.005 Ca 0.585 Ta 0.410 12 470 670 ⊚ 400 PLD 36 —0.000 Ca 1.000 — 0.000 9 840 1250 ◯ 400 PLD

Samples No. 1 to 31

According to Table 1, Samples No. 1 to 31 were dielectric filmscontaining A_(α)B_(β)C_(2γ)O_(α+β+5γ) (wherein A represents Ba, Brepresents at least one element selected from the group consisting of Caand Sr, and C represents at least one element selected from the groupconsisting of Ta and Nb) and the relationships of α, β and γ in thesesamples were as follows, i.e., α+β+γ=1.000, 0.000<α≦0.375, 0.625≦β<1.000and 0.000≦γ≦0.375. It was confirmed that the Samples No. 1 to 31 hadexcellent properties, wherein, the relative permittivity was 11 orabove, the Q value was 500 or above and the dielectric breakdown voltagewas 700V/μm or above.

Samples No. 2, 4, 6, 8, 9, 11 to 31

According to Table 1, Samples No. 2, 4, 6, 8, 9, 11 to 31 weredielectric films containing A_(α)B_(β)C_(2γ)O_(α+β+5γ) (wherein Arepresents Ba, B represents at least one element selected from the groupconsisting of Ca and Sr, and C represents at least one element selectedfrom the group consisting of Ta and Nb) and the relationships of α, βand γ in these samples were as follows, i.e., α+β+γ=1.000,0.000<α≦0.375, 0.625≦β<1.000 and 0.000<γ≦0.375. It was confirmed that inthe Samples No. 2, 4, 6, 8, 9, 11 to 31, the relative permittivity was11 or above, the Q value was 500 or above, the dielectric breakdownvoltage was 700V/μm or above and further the moisture resistance wasalso excellent.

Samples No. 6, 8, 11, 13, 14, 16, 19 to 31

According to Table 1, it could be confirmed that in Samples No. 6, 8,11, 13, 14, 16, 19 to 31 where the relationships of α, β and γ in thesesamples were as follows, i.e., α+β+γ=1.000, 0.100≦α≦0.375, 0.625≦β≦0.900and 0.000<γ≦0.275, a higher relative permittivity could be obtainedwhile the Q value and the dielectric breakdown voltage were maintained.

Samples No. 2, 8, 9, 12 to 14, 17 to 19, 21 to 31

According to Table 1, it could be confirmed that in Samples No. 2, 8, 9,12 to 14, 17 to 19, 21 to 31 where the relationships of α, β and γ inthese samples were as follows, i.e., α+β+γ=1.000, 0.000<α≦0.180,0.770≦β<1.000 and 0.000<γ≦0.050, a higher Q value could be obtained withthe relative permittivity and the dielectric breakdown voltagemaintained.

Samples No. 2, 11 to 14, 18, 20, 21 to 31

According to Table 1, it could be confirmed that in Samples No. 2, 11 to14, 18, 20, 21 to 31 where the relationships of α, β and γ in thesesamples were as follows, i.e., α+β+γ=1.000, 0.000<α≦0.215, 0.770≦β<1.000and 0.000<γ≦0.015, a higher dielectric breakdown voltage could beobtained while the relative permittivity and the Q value weremaintained.

Samples No. 13, 14, 21 to 31

According to Table 1, it could be confirmed that in Samples No. 13, 14,21 to 31 where the relationships of α, β and γ in these samples were asfollows, i.e., α+β+γ=1.000, 0.100≦α≦0.180, 0.805≦β≦0.900 and0.000<γ≦0.015, all of properties of the relative permittivity, the Qvalue and the dielectric breakdown voltage could obtain a higher value.

Samples No. 21, 22 and 23

According to Table 1, it could be confirmed that Samples No. 21 where Tawas selected as C, Samples No. 22 where both Ta and Nb were selected andSamples No. 23 where Nb was selected showed similar properties, wherein,all of the three samples were dielectric films containingA_(α)B_(β)C_(2γ)O_(α+β+5γ) (wherein A represents Ba, B represents atleast one element selected from the group consisting of Ca and Sr, and Crepresents at least one element selected from the group consisting of Taand Nb).

Samples No. 21, 24 and 27

According to Table 1, it could be confirmed that Samples No. 21 where Cawas selected as B, Samples No. 24 where both Ca and Sr were selected andSamples No. 27 where Sr was selected showed similar properties, wherein,all of the three samples were dielectric films containingA_(α)B_(β)C_(2γ)O_(α+β+5γ) (wherein A represents Ba, B represents atleast one element selected from the group consisting of Ca and Sr, and Crepresents at least one element selected from the group consisting of Taand Nb).

Samples No. 21, 22 to 29

According to Table 1, it could be confirmed that Samples No. 21, 22 to29, where the combination of the selected elements as B and C werevarious, showed similar properties, wherein, all of the samples weredielectric films containing A_(α)B_(β)C_(2γ)O_(α+β+5γ) (wherein Arepresents Ba, B represents at least one element selected from the groupconsisting of Ca and Sr, and C represents at least one element selectedfrom the group consisting of Ta and Nb).

Samples No. 21, 30, 31

According to Table 1, it could be confirmed that the samples would showsimilar properties by using the dielectric film of the presentembodiment as long as the compositions were the same even if thethicknesses of the dielectric film were different.

Example 2

A sample was prepared using the same method as Sample No. 21 of Example1 except a sputtering method was used to depositing the film and sameevaluation as in Example 1 was carried out. The results were shown inTable 2.

TABLE 2 relative Q film film Sample permittivity value Vbd moisturethickness forming No. A α B β C γ (—) (—) (V/μm) resistance (nm) methodExample 1 21 Ba 0.140 Ca 0.852 Ta 0.008 14 790 1240 ⊚ 400 PLD Example 237 Ba 0.140 Ca 0.852 Ta 0.008 14 800 1300 ⊚ 400 Sputtering

Samples No. 21, 37

According to Table 2, it could be confirmed that the samples would showsimilar properties by using the dielectric film of the presentembodiment as long as the compositions were the same even if thepreparation methods of the dielectric film were different.

As described above, the present invention relates to a dielectriccomposition and an electronic component. In particular, the presentinvention provides a dielectric composition and an electronic componentusing this dielectric composition, in which the dielectric compositionand the electronic component have a high relative permittivity, a high Qvalue, and a high dielectric breakdown voltage even when under a highfrequency (2 GHz). In this respect, the electronic component using thedielectric composition can be downsized and provided with excellentperformance. The present invention widely provides novel technologies toa film component working at a high frequency which uses dielectric filmssuch as a diplexer or a band-pass filter or the like.

DESCRIPTION OF REFERENCE NUMERALS

-   1 Supporting substrate-   2 Foundation layer-   3 Lower electrode-   4 Upper electrode-   5 Dielectric film-   10 Film capacitor

What is claimed is:
 1. A dielectric composition comprising a complexoxide represented by a formula of A_(α)B_(β)C_(2γ)O_(α+β+5γ) as maincomponent, wherein, A represents Ba, B represents at least one elementselected from the group consisting of Ca and Sr, C represents at leastone element selected from the group consisting of Ta and Nb, α, β and γmeet the following conditions: α+β+γ=1.000, 0.000<α≦0.375,0.625≦β<1.000, and 0.000≦γ≦0.375, and the dielectric composition is in aform of a film having a thickness of 10 nm to 2000 nm.
 2. The dielectriccomposition of claim 1 comprising the complex oxide as the maincomponent, wherein, in the formula, α, β and γ meet the followingconditions: α+β+γ=1.000, 0.000<α≦0.375, 0.625≦β<1.000, and0.000<γ≦0.375.
 3. The dielectric composition of claim 1 comprising thecomplex oxide as the main component, wherein, in the formula, β, β and γmeet the following conditions: α+β+γ=1.000, 0.100≦α≦0.375,0.625≦β≦0.900, and 0.000<γ≦0.275.
 4. The dielectric composition of claim1 comprising the complex oxide as the main component, wherein, in theformula, β, β and γ meet the following conditions: α+β+γ=1.000,0.000<α≦0.180, 0.770≦β<1.000, and 0.000<γ≦0.050.
 5. The dielectriccomposition of claim 1 comprising the complex oxide as the maincomponent, wherein, in the formula, β, β and γ meet the followingconditions: α+β+γ=1.000, 0.000<α≦0.215, 0.770≦β<1.000, and0.000<γ≦0.015.
 6. The dielectric composition of claim 1 comprising thecomplex oxide as the main component, wherein, in the formula, β, β and γmeet the following conditions: α+β+γ=1.000, 0.100≦α≦0.180,0.805≦β≦0.900, and 0.000<γ≦0.015.
 7. An electronic component comprisingthe dielectric composition of claim
 1. 8. An electronic componentcomprising the dielectric composition of claim
 2. 9. An electroniccomponent comprising the dielectric composition of claim
 3. 10. Anelectronic component comprising the dielectric composition of claim 4.11. An electronic component comprising the dielectric composition ofclaim
 5. 12. An electronic component comprising the dielectriccomposition of claim
 6. 13. The dielectric composition of claim 1,wherein the film has a thickness of from 50 nm to 1000 nm.